Water line cathodic protection unit



FIG. 1 is a top and right side perspective view of a water line cathodic protection unit;

FIG. 2 is a left side elevation, the right side being a mirror image;

FIG. 3 is a top plan view;

FIG. 4 is a front end elevation;

FIG. 5 is a rear end elevation; and,

FIG. 6 is a bottom plan view. 

The ornamental design for a water line cathodic protection unit, as shown. 